Please follow directions.
School Subject:______________ (Examples: math, science, algebra, geography)
Coal is carried from a mine in West Virginia to a power plant in New York in hopper cars on a long train. The automatic hopper car loader is set to put 55 tons of coal into each car. The actual weights of coal loaded into each car are normally distributed, with mean ì = 55 tons and standard deviation ó = 0.8 ton.
What is the probability that one car chosen at random will have less than 54.5 tons of coal? (Round your answer to four decimal places.)
What is the probability that 37 cars chosen at random will have a mean load weight x bar of less than 54.5 tons of coal? (Round your answer to four decimal places.)
2 answers
1. Z = (score-mean)/SD
Find table in the back of your statistics text labeled something like "areas under normal distribution" to find the proportion/probability related to the Z score.
2. Z = (score-mean)/SEm
SEm = SD/√n
Use same table.
Find table in the back of your statistics text labeled something like "areas under normal distribution" to find the proportion/probability related to the Z score.
2. Z = (score-mean)/SEm
SEm = SD/√n
Use same table.
1 answer